Measurements of the Electric and Magnetic Form Factors of the Neutron for Timelike Momentum Transfer
Küçük Resim Yok
Tarih
2023
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Physical Soc
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
We present the first measurements of the electric and magnetic form factors of the neutron in the timelike (positive q2) region as function of four-momentum transfer. We explored the differential cross sections of the reaction e+e- -> n over bar n with data collected with the BESIII detector at the BEPCII accelerator, corresponding to an integrated luminosity of 354.6 pb-1 in total at twelve center-of-mass energies ffiffibetweenps = 2.0-2.95 GeV. A relative ffiffiuncertainty of 18% and 12% for the electric and magnetic form factors, respectively, is achieved at ps= 2.3935 GeV. Our results are comparable in accuracy to those from electron scattering in the comparable spacelike region of four-momentum transfer. The electromag-netic form factor ratio Rem equivalent to IGEI=IGMI is within the uncertainties close to unity. We compare our result on IGEI and IGMI to recent model predictions, and the measurements in the spacelike region to test the analyticity of electromagnetic form factors.
Açıklama
Anahtar Kelimeler
Dispersion-Theoretical Analysis, Annihilation, Scattering, Collider
Kaynak
Physical Review Letters
WoS Q Değeri
N/A
Scopus Q Değeri
Q1
Cilt
130
Sayı
15
